for the government went on television saying, we might need help of u.s. military fighting the nuclear accident. already, 750 of the nuclear plant workers had been told to leave, to find a safe place. only about 50 had remained. and now, it's believed, even they had been told to stop for a time. japanese officials had begun using helicopters to drop water on one of the reactors. now, even that idea is deemed unlikely to work. pictures this morning show the helicopters trying. they had to stop. it's believed the last 50 workers were already the final line of defense, working frantic in an all-out race. and nuclear experts tell us they're likely using full body suits with air packs, rotating in and out. radiation sickness can begin to set in rapidly at levels of 1,000 millisieverts. that's the equivalent of 25,000 chest x-rays. if exposed, the symptoms are immediate. right now, the radiation levels have retreated slightly to ten millisievert. equivalent of one c.t. scan for every hour of exposure. overnight, reactor number 4 caught on fire for a second time in 24 hours. one reactor exploded after
